Liquid Immersion Cooled Multichip Module

1. A liquid immersion cooled multichip module comprising: a) a printed circuit board; b) a substrate having a plurality of chips mounted thereon and being adapted to mount with the printed circuit board; c) a lid adapted to be secured to the printed circuit board so as to mount with the substrate to form a fluid chamber between the lid and the substrate, and to cause the substrate to mate with the printed circuit board; d) a bolster plate on a side of the printed circuit board opposite the lid, the lid being fastened to the bolster plate to secure the lid to the printed circuit board; and e) a baffle within the lid constructed to direct a flow of coolant through the fluid chamber, the baffle being constructed to direct a flow of coolant through the lid along a generally U-shaped flow path having an inbound segment leading to a transition segment followed by an outbound segment, the outbound segment supplying coolant fluid over the plurality of chips so as to provide a parallel flow over a first set of chips followed by a series flow over a downstream chip, the inbound segment supplying a partial flow of coolant laterally across an adjacent chip of the first set of chips so as to combine with the parallel flow.

2. The multichip module of claim 1 , wherein the bolster plate is a cambered bolster plate.

3. The multichip module of claim 1 , wherein the baffle further comprises a ramp down region positioned adjacent the first set of chips.

4. The multichip module of claim 1 , wherein the baffle further comprises a flow separator adjacent to the first set of chips.

5. The multichip module of claim 1 further comprising an O-ring between the lid and the substrate, and wherein the lid is secured to the bolster plate using a threaded fastener to compress the O-ring between the lid and the substrate to seal the fluid chamber.

6. The multichip module of claim 1 , wherein the lid further comprises a fluid inlet and a fluid outlet, the fluid inlet and fluid outlet being located on a same peripheral edge the lid.

7. A liquid immersion cooled multichip module comprising: a) a printed circuit board; b) a substrate having a plurality of chips mounted thereon and being adapted to mount with the printed circuit board; c) a lid adapted to be secured to the printed circuit board so as to mount with the substrate to form a fluid chamber between the lid and the substrate, and to cause the substrate to mate with the printed circuit board; d) a cambered bolster plate on a side of the printed circuit board opposite the lid, the lid being fastened to the cambered bolster plate to secure the lid to the printed circuit board; and e) the lid comprising a baffle therein constructed to direct a flow of coolant through the fluid chamber, the baffle being constructed to direct a flow of coolant through the lid over the plurality of chips so as to provide a parallel flow over a first set of chips followed by a series flow over a downstream chip.

8. The multichip module of claim 7 , wherein the baffle further comprises a ramp down region positioned adjacent the first set of chips.

9. The multichip module of claim 7 , wherein the baffle further comprises a flow separator adjacent to the first set of chips.

10. The multichip module of claim 7 further comprising an o-ring between the lid and the substrate, and wherein the lid is secured to the cambered bolster plate using a threaded fastener to compress the O-ring between the lid and the substrate to seal the fluid chamber.

11. The multichip module of claim 7 , wherein the lid further comprises a fluid inlet and a fluid outlet, the fluid inlet and the fluid outlet being located on a same peripheral edge the lid.

12. The multichip module of claim 7 , wherein the baffle is removable from the lid.

13. A liquid immersion cooled multichip module comprising: a) a printed circuit board; b) a substrate having a plurality of chips mounted thereon and being adapted to mount with the printed circuit board; c) a lid adapted to be secured to the printed circuit board so as to mount with the substrate to form a fluid chamber between the lid and the substrate, and to cause the substrate to mate with the printed circuit board; d) a bolster plate on a side of the printed circuit board opposite the lid, the lid being fastened to the cambered bolster plate to secure the lid to the printed circuit board; e) a coolant fluid inlet and outlet located on a same peripheral edge the lid; and f) a removable baffle within the lid constructed to direct a flow of coolant through the fluid chamber.

14. The multichip module of claim 13 , wherein the bolster plate is a cambered bolster plate.

15. The multichip module of claim 13 , wherein the baffle further comprises a ramp down region positioned adjacent the plurality of chips.

16. The multichip module of claim 13 further comprising an O-ring between the lid and the substrate, the lid being secured to the bolster plate using a threaded fastener to compress the O-ring between the lid and the substrate to seal the fluid chamber.

17. The multichip module of claim 13 , wherein the lid further comprises a fluid inlet and a fluid outlet, the fluid inlet and fluid outlet being located on a same peripheral edge the lid.

18. The multichip module of claim 13 , wherein the baffle is constructed to direct a flow of coolant through the lid over the plurality of chips so as to provide a parallel flow over a first set of chips followed by a series flow over a downstream chip.

19. The multichip module of claim 13 , wherein the baffle is constructed to direct a flow of coolant through the lid along a generally U-shaped flow path having an inbound segment leading to a transition segment followed by an outbound segment, the outbound segment supplying coolant fluid over the plurality of chips so as to provide a parallel flow over a first set of chips followed by a series flow over a downstream chip, the inbound segment supplying a partial flow of coolant laterally across an adjacent chip of the first set of chips to combine with the parallel flow.

20. The multichip module of claim 13 , wherein the baffle is constructed to direct a flow of coolant through the lid over the plurality of chips so as to provide a series flow over the plurality of chips.